Rare Presentation of Subclinical Hypothyroidism from a Lingual Thyroid
A 25-year-old female, presented with a posterior lingual mass, without pain nor bleeding (Figure 1). She became more prone to shortness of breath upon exercise and felt uncomfortable swallowing solid food but denied snoring, cold intolerance, or unintentional weight gain. Examination revealed a mass posterior to her tongue and no palpable thyroid gland at the thyroid fossa. Investigations revealed thyroid function tests (TFTs): FT4 1.29 μg/dl (0.89-1.76); TSH 17,049 IU/ml (0.55-4.78); T3 total 1.27 μg/dl (0.6-1.81). Fiber optic laryngoscopy showed a smooth, slippery, unilocular mass attached to the base of tongue. CT cervical-head showed a high-density 2.6 x 2.2 x 2 cm3 soft tissue mass posterior to the tongue, which narrowed the airway to a diameter of 0.4 cm (Figure 2). The mass was likely to be thyroid tissue. To reduce the obstructive symptoms from the mass we did excisional surgery followed by the administration of levothyroxine 25 μg once daily. She had no complaints after surgery. A follow-up thyroid function profile showed FT4 1.46; TSH 6.467; T3 1.59. Histopathology of the tissue revealed multiple thyroid follicles consistent with ectopic thyroid (Figure 3).
The ectopic thyroid is a rare congenital disorder with incidence between 1:3000- 1:300000 although it could present with thyroid dysfunction. Most ectopic thyroid cases are euthyroid, only a few patients are subclinically hypothyroid.1 It is usually aysmptomatic but as the mass increases it can cause obstructive symptoms.2 At the age of puberty, thyroid hormone deficiency causes hypertrophic glands and results in obstructive symptoms. Asymptomatic cases can be monitored with serial exams or receive hormonal therapy with levothyroxine. However, such treatment does not have a good success rate. The reduction in size occurs very slowly, without significant decreases in volume. 1 Therefore, the decision to excise the mass was made for this patient. After surgery, monitoring of symptoms and thyroid hormone levels should be done regularly. Levothyroxine supplementation is recommended to prevent overt hypothyroidism and to suppress production of TSH.3,4
Xavier CRS, Medeiros LFB, Freire AD, et al. Lingual thyroid – Literature review. Arch Med. 2016. https://www.archivesofmedicine.com/medicine/lingual-thyroidliterature-review.php?aid=9572.
Allen E, Alzeerah M, Tsiao S, Aydin N, Misra S. A unique presentation of ectopic thyroid, a case report. Int J Surg Case Rep. 2016;29:185–8. https://pubmed.ncbi.nlm.nih.gov/27866035. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5121164. https://doi.org/10.1016/j.ijscr.2016.10.079.
Alexander EK, Pearce EN, Brent GA, et al. 2017 Guidelines of the American Thyroid Association for the diagnosis and management of thyroid disease during pregnancy and the postpartum. Thyroid. 2017;27(3):315–89. https://pubmed.ncbi.nlm.nih.gov/28056690. https://doi.org/10.1089/thy.2016.0457.
Fatourechi V. Subclinical hypothyroidism: An update for primary care physicians. Mayo Clin Proc. 2009;84(1):65-71. https://pubmed.ncbi.nlm.nih.gov/19121255. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2664572. https://doi.org/10.1016/S0025-6196(11)60809-4.
Copyright (c) 2021 Choirina Windradi, Soebagijo Adi Soelistijo, Sony Wibisono Mudjanarko, Muhtarum Yusuf
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Journal of the ASEAN Federation of Endocrine Societies is licensed under a Creative Commons Attribution-NonCommercial 4.0 International. (full license at this link: http://creativecommons.org/licenses/by-nc/3.0/legalcode).
To obtain permission to translate/reproduce or download articles or use images FOR COMMERCIAL REUSE/BUSINESS PURPOSES from the Journal of the ASEAN Federation of Endocrine Societies, kindly fill in the Permission Request for Use of Copyrighted Material and return as PDF file to firstname.lastname@example.org or email@example.com.
A written agreement shall be emailed to the requester should permission be granted.